Keyboards are generally known in the art for allowing a user input to an electronic device. Keyboards include several keys positioned within several indentations or openings within a top portion of the keyboard. The keys may be electrically connected to a substrate (e.g., printed circuit board) located within the electronic device. The substrate generally includes dimensions (e.g., length and width) similar to that of the keyboard. In other words, at least a portion of the substrate is positioned below each key. The substrate may include several switches or other components such that when a key is depressed, one of the switches or other components is actuated. This actuation may correspond to the user input to the electronic device.
However, keyboards using substrates in this manner have several disadvantages. For example, a substrate having similar dimensions to that of the keyboard uses a large portion of limited space within the keyboard. This reduces the amount of space available for other components, and in addition, may create difficulties in reducing the overall footprint of the keyboard. Also, in order for the substrate to receive the user input, each indentation that receives a key must include an opening such that one or more components (e.g., keycap, switch) may protrude through the opening and connect to the substrate. These openings allow for ingress of contaminants (e.g., dust, liquids) to propagate to various components within the keyboard and/or the electronic device, which may result in damage to or failure of the electronic device. Also, the openings necessarily result in removal of material from the keyboard causing a reduction in the overall rigidity of the keyboard. Accordingly, the keyboard may appear less sturdy to a user.
The substrate also occupies an area that could otherwise be used to receive other internal components, such as an interior portion of the keyboard located on a portion opposite the indentations. As a result, some internal components that generate heat within the electronic device are in close proximity to other internal components vulnerable to heat.